Cutting apparatus

1. A cutting apparatus comprising: a first X-axis guide rail extended along an X-axis direction; a first chuck table that is disposed movably along the first X-axis guide rail and has a first holding surface to hold a first workpiece; a first cutting feed mechanism that carries out cutting feed of the first chuck table along the first X-axis guide rail; a second X-axis guide rail extended along the X-axis direction; a second chuck table that is disposed movably along the second X-axis guide rail and has a second holding surface to hold a second workpiece; a second cutting feed mechanism that carries out cutting feed of the second chuck table along the second X-axis guide rail; first and second Y-axis guide rails that are so disposed as to extend along a direction perpendicular to the first and second X-axis guide rails; a cutting mechanism that is disposed movably along the first and second Y-axis guide rails and is to cut the first and second workpieces held by the first and second chuck tables; and a gate-shaped support frame having a pair of support column parts that sandwich the first and second X-axis guide rails and are provided upright opposed to each other and a guide rail unit that straddles the first and second X-axis guide rails and spans a space between the pair of support column parts, the gate-shaped support frame having an opening that permits movement of the first and second chuck tables, wherein the first Y-axis guide rail extends on a first side surface of the guide rail unit and the second Y-axis guide rail extends on a second side surface of the guide rail units, said cutting mechanism includes a first cutting unit having a first cutting blade, and a second cutting unit having a second cutting blade that are each disposed movably along the first Y-axis guide rail, and a third cutting unit having a third cutting blade and a fourth cutting unit having a fourth cutting blade that are each disposed movably along the second Y-axis guide rail, the first cutting unit has a first indexing feed base movably disposed in a direction along the first Y-axis guide rail, a first cutting feed base disposed over the first indexing feed base movably in a direction perpendicular to the first holding surface of the first chuck table, and a first spindle that is mounted to the first cutting feed base and has the first cutting blade, the second cutting unit has a second indexing feed base movably disposed in a direction along the first Y-axis guide rail, a second cutting feed base disposed over the second indexing feed base movably in a direction perpendicular to the first and second holding surfaces of the first and second chuck tables, and a second spindle that is mounted to the second cutting feed base and has the second cutting blade, the first spindle and the second spindle are disposed opposed to each other in a hung state in the opening of the gate-shaped support frame in such a manner that the first cutting blade and the second cutting blade face each other on the first chuck table, and cut said first workpiece on the first holding surface, wherein the first cutting blade and the second cutting blade cut said first workpiece in the same stroke by a dual-cutting facing dual spindle method, the third cutting unit has a third indexing feed base movably disposed in a direction on the second Y-axis guide rail, a third cutting feed base disposed over the third indexing feed base movably in a direction perpendicular to the first and second holding surfaces of the first and second chuck tables, and a third spindle that is mounted to the third cutting feed base and has the third cutting blade, the fourth cutting unit has a fourth indexing feed base movably disposed in a direction along the second Y-axis guide rail, a fourth cutting feed base disposed over the fourth indexing feed base movably in a direction perpendicular to the second holding surface of the second chuck table, and a fourth spindle that is mounted to the fourth cutting feed base and has the fourth cutting blade, the third spindle and the fourth spindle are disposed opposed to each other in a hung state in the opening of the gate-shaped support frame in such a manner that the third cutting blade and the fourth cutting blade face each other on the second chuck table, and cut said second workpiece, wherein the third cutting blade and the fourth cutting blade cut said second workpiece in the same stroke by the dual-cutting facing dual spindle method, the first spindle and the third spindle are movable in juxtaposition to each other in the opening of the gate-shaped support frame and the first and third cutting blades cut said first workpiece on said first holding surface, wherein the first cutting blade partially cuts said first workpiece to make a first cut groove, and the third cutting blade cuts into said first cut groove to divide said first workpiece by a parallel dual spindle method, and the second spindle and the fourth spindle are movable in juxtaposition to each other in the opening of the gate-shaped support frame and said second and fourth cutting blades cut said second workpiece on the second holding surface, wherein the second cutting blade partially cuts said second workpiece to make a second cut groove, and the fourth cutting blade cuts into said second cut groove to divide said second workpiece by the parallel dual spindle method.

2. The cutting apparatus according to claim 1 , wherein at least two X-axis guide rails are juxtaposed as the X-axis guide rail and the cutting feed mechanism and the chuck table are disposed over each of the X-axis guide units.